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Systém a Evoluce Obratlovců VI. Craniata Vs. Vertebrata

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Systém a Evoluce Obratlovců VI. Craniata Vs. Vertebrata Systém a evoluce obratlovců VI. Craniata vs. Vertebrata Tradiční třídění obratlovců (Vertebrata) Kritérium: ekologické Pisces Tetrapoda (ploutvovci) (čtyřnožci) embryologické Anamnia Amniota (bezblanní) (blanatí) anatomické Agnatha Gnathostomata (bezčelistnatci) (čelistnatci) standardní systém 1: podkmen: Vertebrata - obratlovci (= Craniata - lebečnatci) nadtřída: Agnatha – bezčelistnatci (parafyletický taxon) třída: Ostracodermi † - štítnatci (parafyletický taxon) Cyclostomata – kruhoústí (polyfyletický taxon?) nadtřída: Gnathostomata - čelistnatci třída: Placodermi † - pancířnatci Acanthodii † - trnoploutví Chondrichthyes - paryby Osteichthyes (Pisces) - ryby (parafyletický taxon) Amphibia - obojživelníci Reptilia - plazi (parafyletický taxon?) Aves - ptáci Mammalia - savci standardní systém 2: Craniata Myxinoidea - sliznatky „Vertebrata“ - obratlovci Agnatha - bezčelistnatci podle: Cephalospidomorphi - štítohlaví (hlavoštítí) Moy-Thomas Pteraspidomorphi - štítoploutví (ploutvoštítí) &Milles(1975) Gnathostomata - čelistnatci Placodermi - pancířnatci Chondrichthyes - paryby Acanthodii - trnoploutví Osteichthyes (Pisces) - ryby Actinopterygii - paprskoploutví Sarcopterygii - násadcoploutví Amphibia - obojživelníci Amniota - blanatí (Reptilia, Aves, Mammalia) Myxinoidea - sliznatky CRANIATA „Ostracodermi“ † Conodonta - konodonti - štítnatci †Arandaspida „Agnatha – bez † Heterostraci „Pteraspidomorphi“ †Thelodonti štítoploutví Cyclostomata + č -kruhoústí Petromyzontida - mihule Vertebrata - obratlovci elistnatci“ †Anaspida-birkenie †Galeaspida „Cephalaspidomorphi“ † Osteostraci hlavoštítí Gnathostomata †Placodermi-pancířnatci „Elasmobranchiomorphi“ Chondrichthyes - paryby † Acanthodii - trnoploutví Osteognatho- Teleostomi stomata - Actinopterygii - paprskoploutví č elistnatci Sarcopterygii VERTEBRATA Myllokungmingia † Myxinoidea CYCLOSTOMATA Petromyzontida Conodonta † „Agnatha“ Arandaspida †, Astraspida † Heterostraci † Anaspida † Galeaspida † Thelodonti † Osteostraci † GNATHOSTOMATA „Agnatha“ - vymřelé skupiny 1 5-30 cm † Conodonta - konodonti †Arandaspida † Conodonta †Arandaspida kambrium - Anglie, J-Afrika 50 x1,5mm Anatolepis - kambrium Wyoming, ordovik Kost, myotomy, velké oči - encefalizace Špicberky †Arandaspida Sacabambaspis Hlavová část těla kryta dorzální a ventrální deskou z kostěných štítků Sacabambaspis ordovik - Bolívie „Agnatha“ - vymřelé skupiny 2 †Arandaspida † Heterostraci † Heterostraci - štítoploutví Pteraspis devon – Anglie, párové nozdry, 1 pár žab. štěrb. prsní přívěsky hypocerkní ploutev Hlavová část těla kryta dorzální a ventrální deskou z kostěných štítků „Agnatha“ - vymřelé skupiny 3 † Heterostraci †Anaspida-birkenie †Galeaspida bez hlavového štítu †Anaspida- birkenie Pharyngolepis Pterolepis někdy sesterská skupina k mihulím nebo čelistnatcům, párové přívěsky, hypocerkní ploutev, skupiny drobných štítků, za hlavou párová linie 10 žaberních otvorů †Galeaspida -devon Čína, Vietnam, perichondriální kost (někdy k Osteostraci) „Agnatha“ - vymřelé skupiny 4 †Galeaspida †Thelodonti bez hlavového štítu † Osteostraci † Gnathostomata †Thelodonti párové prsní přívěsky, drobné štítky na těle, hypocerkní ploutev, skupina žaberních otvorů, Někdy považováni za příbuzné k Anaspida a Cyclostomata Phlebolepis „Agnatha“ - vymřelé skupiny 5 †Thelodonti † Osteostraci † Osteostraci - štítohlaví † Gnathostomata - silur-devon, sladkovodní, široký hlavový štít a destičky na trupu z dentinu pokrytého látkou podobnou sklovině, perichondriální osifikace, celulární kost - remodulace, preadaptace ke zvětšování těla, heterocerkní ploutev, benticky - zespodu ploší, očínahoře, shora na hlavě 3 políčka ze štítků chránicích kanálky (hlavové nervy, postranní čára, elektrorecepce?), na dně hltanu destičky – pohyblivost, drcení potravy Cephalaspis Ateleaspis Hemicyclaspis Morf. (paleont.) Morf. (jen rec.) Gen (rec.) Myxinoidea Myxinoidea Myxinoidea Myxinoidea Petromyzontida Petromyzontida Petromyzontida Petromyzontida Gnathostomata Gnathostomata Gnathostomata Vertebrata Craniata „Cyclostomata“ versus Cyclostomata • velké mezery ve fosilním záznamu (chybí kostní tkáň) •3 přežívající linie obratlovců (sliznatky, mihule, čelistnatci) se oddělily během pouhých 40 mil. let ►málo času na nahromadění diagnostických synapomorfií •evolučně velmi staré linie – kambrium (před 500 mil. lety) ► hodně času na nahromadění autapomorfií (přemazání fylogenetického signálu) • málo sdílených odvozených znaků (na úrovni 3 kladů) Paleontologická data: „Cyclostomata“ – parafyletický taxon Anatomická a molekulární data: Cyclostomata – monofyletický taxon Myxinoidea (Hyperotreti) - sliznatky Myxinoidea Petromyzontida •primárně mořské (chladná moře) - tělní tekutiny s vysokým obsahem solí; isotonické s mořskou vodou (OSMOKONFORMITA) • metamerní žlázy, sliz - ochrana •hvězdicovitá ústa s 3 páry hmatových tentakulí a odontoidy, redukované oči • nepárová nozdra, voda nasávána nasohypofyzární chodbou • periodický hermafroditismus, vnější oplození, opakovaná reprodukce • hltan s trávicí i dýchací funkcí • jen levá Cuvierova chodba •43 druhů 6 rodů, Myxine, Bdellostoma Myxinoidea - sliznatky Dýchací aparát žaberní váčky uvnitř koše z chrupavčitých žaberních prstenců, ústí samostatně na povrch, nebo do společného kanálku, hltan nerozdělen na trávicí a dýchací část Myxinoidea - sliznatky Příjem potravy Bdellostoma (80 cm) Potrava: mrtvé nebo poraněné ryby, červi, měkkýši, členovci odontoidy jen na dvojlaločném jazyku - funguje jako čelisti; prolezou skřelemi ryb, nebo se provrtávají přes tělní stěnu a vyžírají vnitřnosti Myxinoidea - sliznatky Rozmnožování Myxine (50 cm) Gonáda - dlouhý pás podél střeva, vpředu: mesovarium ♀♂ , vzadu mesorchium Petromyzontida (Petromyzontes, Petromyzones, Hyperartia) - mihule Myxinoidea Petromyzontida druhotně bez exoskeletu a párovitých přívěsků (karbon Mayomyzon), jen chrupavčitý endoskelet, arcualia, přísavný kruhový ústní terč s odontoidy, pololebka, 9(7) párů žaberních oblouků a 7 párů žaberních otvůrků za hlavou, nepárový čichový ústroj, dorzální a ventrální kořeny se nespojují v míšní nervy - alternují, 1. duplikace Hox genů; 41 druh (z toho 9 potamotokních a 32 sladkovodních). Petromyzontida - mihule Mozek pětidílný (u minoh 3-dílný- telencephalon, diencephalon a tegmentum), velký diencephalon (hypothalamus) Žilné srdce - sinus venosus, atrium, ventriculus, conus a bulbus arteriosus, jen pravý ductus Cuvieri X Petromyzontida - mihule U mihulí je dýchací část hltanu se 7 páry vnitřních žaberních skulin oddělena od trávicí části, u minoh jsou trávicí i dýchací cesty v hltanu společné (viz sliznatky), žaludek chybí, ve střevě spirální řasa trávicí část hltanu dýchací část hltanu Stavba žaber podobnější parybám nežli sliznatkám žaberní váček Petromyzontida - mihule rozmnožování a ontogeneze: minoha metamorfóza minoha dospělá mihule oplození vnější, po tření hynou, nepřímý vývoj - larva minoha příjem potravy: Petromyzontida - mihule minoha - filtrace detritu, dospělci - zvláštní typ predace - přisávají se na ryby, ozubeným ústním terčem a jazykem narušují kůži ryb a nasávají kašovitou svalovinu s krví, nebo potravu vůbec nepříjímají (některé sladkovodní druhy). Myxinoidea-sliznatky Petromyzontida-mihule Gnathostomata-čelistnatci •jen chorda • jen základy neurálních •obratle oblouků obratlů (arcualia) • metamerní slizové žlázy •jen slizovébuňky •slizovébuňky (vodní), kožní žlázy (suchozemští) • 1 polokružná chodba (sek) • 2 polokružné chodby • 3 polokružné chodby • nasohypofyzární chodba • nasohypofyzární vak • bez spojení s hypofýzou •dorz.a ventrálníkořeny •kořeny míšních nervů se •dorz.a ventrálníkořeny se spojují v míšní nerv nespojují, alternují se spojují v míšní nerv • jen levý ductus Cuvieri • jen pravý ductus Cuvieri • oba ducti Cuvieri • osmokonformita • osmoregulace • osmoregulace • jen chrupavka • chrupavka+celulární kost • 9(7) párů žaberních oblouků • čelisti • jen nepárový ploutevní lem (u vymřelých • párové končetiny prsní ploutve) • nepárová nozdra • párové nozdry (5-15) • žábry ve váčcích (7) • žábry na přepážkách nebo na obloucích, plíce ♀ ^ ♂ • nepárová gonáda bez vývodů ♀ v ♂ • párové gonády • rohovité odontoidy v savých ústech • složitý jazykový aparát Co sliznatky dále nemají (vymizení znaků = apomorfie?) •hřbetní ploutev • inervaci srdce (jen autonomie) • čočku, okohybné svaly a jejich nervy •slezinu • neuromasty •svaly v ocasníploutvi • elektrorecepci • žaberní oblouky (jen prstence) • chuťové pohárky Čím dále se sliznatky odlišují ? •oběhový systém má přídatná venózní „srdce“ (plesiomorfie) • perikardiální dutina a célom propojené (uzavřené u mihulí a čelistnatců) • část lebky z vláknité tkáně • jediný typ leukocytů (chybí lymfocyty) • difúzní adenohypofýza •tentakule •velum Nejsou známy: struktura a charakter působení nervové lišty!.
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